+

WO2001032571A1 - Commencement d'une decoupe de verre au moyen d'un laser - Google Patents

Commencement d'une decoupe de verre au moyen d'un laser Download PDF

Info

Publication number
WO2001032571A1
WO2001032571A1 PCT/US2000/029279 US0029279W WO0132571A1 WO 2001032571 A1 WO2001032571 A1 WO 2001032571A1 US 0029279 W US0029279 W US 0029279W WO 0132571 A1 WO0132571 A1 WO 0132571A1
Authority
WO
WIPO (PCT)
Prior art keywords
brittle material
laser
notch
glass
thermal
Prior art date
Application number
PCT/US2000/029279
Other languages
English (en)
Inventor
Dmitri Nikitin
Thomas Michel
Original Assignee
P.T.G. Precision Technology Center Llc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by P.T.G. Precision Technology Center Llc filed Critical P.T.G. Precision Technology Center Llc
Priority to AU12275/01A priority Critical patent/AU1227501A/en
Publication of WO2001032571A1 publication Critical patent/WO2001032571A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B33/00—Severing cooled glass
    • C03B33/09—Severing cooled glass by thermal shock
    • C03B33/091—Severing cooled glass by thermal shock using at least one focussed radiation beam, e.g. laser beam

Definitions

  • the present invention relates to a method of cutting brittle materials.
  • the cutting of glass has been done for centuries. The techniques developed many years ago are still in use today and remain fundamentally unchanged.
  • the method generally consists of scribing a line, conforming to the shape desired, onto the surface to be cut with a material that is much harder than the glass itself, and then breaking the glass along the scribe line.
  • the scribing material is typically made from diamond or zirconia.
  • the scribing action chips away the surface and creates tiny fragments of glass from the glass surface leaving a small groove in the wake of the scribe. This groove creates a localized area of high stress in the glass.
  • the glass tends to fracture along this line when it is stressed beyond its strength threshold.
  • the problem with this method is that the break line is somewhat unpredictable because when the scribe chips the glass flakes away, it does so in an unpredictable and irregular geometry.
  • the best way to control the break line predictability is to make the scribe line as narrow and as deep as possible. There are, however, certain practical limitations as to just how narrow and deep the scribe line can be made. Some of these limitations are: scribe point diameter, scribe point geometry, scribing pressure, homogeneity of the glass substrate material and the velocity of the scribing.
  • Fragile edges limit the ability to safely handle the glass and restrict the use of certain processing steps and equipment. When a fragile edge is stressed (and there is no predictable stress threshold) it can cause the glass to develop a microscopic errant crack, which will grow larger with time. It is not possible to reliably predict how long the crack will take to sufficiently weaken the glass and induce failure. Thermal cycling and exposure to vibration accelerate the crack propagation but not at a predictable rate or along a predictable path. Each glass part has its own individual set of variables. This presents the worst of all possible scenarios, dealing with an unpredictable randomized failure mode. Changes in the scribing velocity, caused by variations of the glass surface (hills and valleys) will vary the effective applied scribing pressure, causing variations in the depth and width of the scribed line.
  • FIGS. 1 and 2 Some of these problems are illustrated in FIGS. 1 and 2, wherein the action of the mechanical scribe 10 moving across the surface of the glass produces airborne glass particles 12, and residual shards of glass 14 on the surface of the glass substrate. Further, the scribed groove 16 is illustrated, showing the ragged edges 18 resulting from the mechanical scribing action.
  • Another disadvantage of scribing is that it creates volumes of tiny glass particles. Unless these particles are collected (adding more equipment and expense to the operation) they may find their way into the air and eventually onto a work surface, or more critically, a device surface.
  • the glass is burned away or evaporated by the heat generated by the laser's beam.
  • the material is severed, one part from the other. This process actually consumes material requiring dimensional parameters to be adjusted for cut losses.
  • the cut-edge of the glass is a melted edge. Melted edges have an unpredictable or irregular geometry. This necessitates post-cut edge processing such as by grinding to the required geometry with a diamond or zirconia abrasive wheel. Such processing is costly in both time and materials and because of vibration, caused by the grinding process, additional shear stresses may be imparted to the glass further increasing the risk of fracture or errant micro-crack formation.
  • This new, laser based, glass (or other brittle material) cutting method does not rely on burning or melting the glass in order to cut it.
  • the method which relies on the thermo-physical properties of glass, uses a laser, in a controlled manner, to heat the glass to a specific temperature stressing it in a controlled manner, and then re-stressing it with a cooling jet.
  • the method embodies the creation of controlled sub-surface stresses within the glass which are induced by precise laser heating (or other appropriate energy transfer method) and immediate controlled cooling with a water/cool air mist.
  • the heat capacity of the water/air mist quickly removes the localized heat from the glass surface, which was caused by the laser, and thereby induces high tensile stresses deep in the glass body. These stresses overcome the molecular binding forces within the glass and result in the creation of a micro-crack within the molecular structure where the molecules bond, one-to-the- other, in the glass body.
  • the heating and cooling creates stress that generates a micro-crack within the body of the glass with a controlled size (height) which is propagated through the body of the glass, in a plane normal to the glass surface and following the heat/chill path described by the translation of the laser beam/cooling jet across the glass surface which follows the outline of, and describes the shape of, the pattern to be cut from the glass.
  • a bending moment is then applied to the glass, one vector being applied to either side of the "scribed line" on that surface and a pivotal vector being applied in the opposite direction on the opposite surface of the "scribed line".
  • the glass, with the propagated crack, can then be split clean, having none of the disadvantages of the mechanical scribe and break process.
  • advantages to this process like high-speed cutting and the ability to make complex geometric cuts.
  • the glass neatly separates (breaks) following the laser-induced micro-crack that was propagated along and inside the body of the subject glass material with no kerf loss or generated particles.
  • greater advances in cutting efficiency have been hindered by the continued necessity to use the archaic mechanical scribing techniques (described above) to initiate the cut.
  • the laser's thermal ablation "scribe and break line" is clean and repeatable, problems are still encountered during the cut-initiation process.
  • cut-initiation is based on the diamond scribe technique, it brings to the process all of the problems of: glass surface contamination, uncontrolled stresses created in the glass, high variability in notch characteristics, and unpredictability of the break.
  • a method for cutting a brittle material comprising forming a stress plane in the body of the brittle material by applying an energy beam along a cut path, followed by a cooling jet applied to the surface along the cut path to form a micro-crack in the material.
  • the start or initiation point is done by thermal ablation of a tiny point on the surface of the brittle material, at the edge or within the field, at the start of the line to initiate the micro-crack fracture in the material.
  • FIG. 1 illustrates a conventional mechanical scribe method of cutting a brittle material.
  • FIG 2 illustrates an enlarged end view of a mechanically scribed brittle substrate.
  • FIG. 3 illustrates various placements of the laser ablated notch consistent with the present invention.
  • FIG. 4 illustrates a comparison of the geometry of both mechanical crack initiation and laser crack initiation.
  • FIG. 5 illustrates the ablated notch and the micro-crack separation plane.
  • FIG. 6 illustrates the tensile forces generated within the glass when the micro- crack is formed.
  • FIG. 6 a method for initiating the micro-crack in a brittle material 20 is illustrated. This is done by directing a C0 2 (or other laser) beam at the target while maintaining the spot size as small as possible.
  • a micro-crack 24 corresponding to the desired cut line 22 is first formed in the body of the brittle material 20, for example, using a laser beam in accordance with the teachings of US Patent 5,609,284, the content of which is incorporated herein by reference. Thereafter, actual fracture of the brittle material 20 is by thermally or mechanically stressing a surface 28 of the brittle material 20, adjacent an edge thereof.
  • the crack is initiated by the thermal ablation of a notch 26 disposed along the line of, but preceding the micro-crack 24, as is depicted in FIG. 5.
  • the brittle material 20 to be cut may be, but is not limited to, mineral glasses, metal glasses, vitreous silica, ceramics, and crystalline materials.
  • the micro-crack 24 formed within the body of the brittle material 20 is formed by directing a thermal energy beam along a cut path or cut line 22 on the surface of the brittle material 20 followed by a cooling jet to form a micro-crack 24 in a brittle material 20 whereby to heat the brittle material 20 along the desired cut line 22, and subsequently cool the brittle material 20 along the cut line 22.
  • the brittle material 20 is heated by a laser containing appropriate optics to project a beam incident on the surface 28 of the brittle material 20.
  • the brittle material 20 is cooled by a cooling jet traveling in the wake of the laser beam. The resultant thermal stress caused by the heating action of the laser beam and the subsequent cooling of the cooling jet produces a very fine and accurate micro-crack 24 along the path traced by the laser, i.e. the desired cut line 22, in a plane generally perpendicular to the surface 28 of the brittle material 20.
  • a fracture initiation notch 26 illustrated in FIGS.
  • the energy source employed to thermal ablate the surface 28 of the brittle material 20 comprises a laser, and in an even more preferred embodiment the laser comprises a carbon dioxide laser, a NdYAG laser or a deep UV laser.
  • the surface 28 of the brittle material preferably is ablated by the application of an incident laser energy beam focused to a controlled geometric shape so as to form an ablated region in the form of a notch 26.
  • the fracture initiation notch 26 is ablated into the surface 28 of the brittle material 20 adjacent one edge of the brittle material and at the desired point of start of the fracture. That is to say, the ablated fracture initiation notch 26 is formed at the intersection of the edge boundary plane 30 and the surface plane 28, i.e. at a corner of an exterior surface of the brittle material 20.
  • the combined effects of ablative reduction in cross-sectional thickness of the brittle material, thermally induced stress at the ablation site is enough to weaken the brittle material sufficiently for it to allow the laser scribing beam to easily form a micro-crack.
  • the amount of stress produced and the concentration of the stress depends on the geometry and relative size of the notch relative to the brittle material being processed.
  • the stress concentration will not be as great as if the leading edge and bottom are sharply angled. It will therefore be appreciated that the stress concentrating effect, and therefore the required initiation stress, may be controlled by altering the cross-sectional profile and aspect ratio of the notch 26.
  • the preferred method involves a Guassian laser beam which results in a conical notch Guassian profile.
  • the ablation of the surface 28 of the brittle material 20 creates a break in the surface of the brittle material and results in a reduction in cross- sectional thickness of the brittle material, (and the creation of localized high levels of stress), i.e. at the notch 26, much the same as if a notch 26 were mechanically scribed into the surface 28 of the brittle material 20.
  • thermal ablating the surface 28 of the brittle material 20 with a controlled energy beam does not produce chips, airborne particles, or uncontrolled random stress razers.
  • the breaking stress in the notch is predictable and controllable.
  • the application of the controlled energy beam also induces thermal stress in the brittle material 20.
  • the induced thermal stress creates a thermal stress zone 32 that produces an instability in the gross-molecular structure of the brittle material 20 in the immediate, and therefore controllable, area of the energy beam's incident foot print on the surface 28 of the brittle material 20. This thermal stress is converted to mechanical stress.
  • the resultant mechanical stress assists the scribing beam, originating at the notch, to propagate the micro-crack through brittle material 20 along the scribing beam's path. That is to say, the combined effects of ablative reduction of the cross-sectional area of the brittle material 20 and the thermally induced mechanical stress in the material created by the cut initiation laser's coherent light wave front colliding with the target surface, is enough to weaken the brittle material 20 sufficiently to allow easy micro- crack initiation and sustained propagation by the scribing beam.
  • the fracture microwave-crack

Landscapes

  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Optics & Photonics (AREA)
  • Toxicology (AREA)
  • Thermal Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Re-Forming, After-Treatment, Cutting And Transporting Of Glass Products (AREA)
  • Processing Of Stones Or Stones Resemblance Materials (AREA)

Abstract

Un procédé permettant de commencer une rupture dans un matériau fragile et cassant le long d'une microfissure consiste à entailler par voie thermique la surface du matériau fragile et cassant pour former une entaille dans le matériau fragile et cassant à l'endroit désiré pour le point de fracture.
PCT/US2000/029279 1999-11-01 2000-10-24 Commencement d'une decoupe de verre au moyen d'un laser WO2001032571A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU12275/01A AU1227501A (en) 1999-11-01 2000-10-24 Laser driven glass cut-initiation

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US16282699P 1999-11-01 1999-11-01
US60/162,826 1999-11-01

Publications (1)

Publication Number Publication Date
WO2001032571A1 true WO2001032571A1 (fr) 2001-05-10

Family

ID=22587289

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2000/029279 WO2001032571A1 (fr) 1999-11-01 2000-10-24 Commencement d'une decoupe de verre au moyen d'un laser

Country Status (2)

Country Link
AU (1) AU1227501A (fr)
WO (1) WO2001032571A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2238918C2 (ru) * 2002-06-07 2004-10-27 Кондратенко Владимир Степанович Способ резки хрупких неметаллических материалов
US6919531B2 (en) 2002-03-25 2005-07-19 Agilent Technologies, Inc. Methods for producing glass substrates for use in biopolymeric microarrays

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3629545A (en) * 1967-12-19 1971-12-21 Western Electric Co Laser substrate parting
FR2202856A1 (fr) * 1972-10-12 1974-05-10 Glaverbel
GB2139615A (en) * 1983-05-13 1984-11-14 Glaverbel Forming holes in vitreous sheets
WO1993020015A1 (fr) * 1992-04-02 1993-10-14 Fonon Technology Limited Clivage de materiaux non metalliques
WO1997007927A1 (fr) * 1995-08-31 1997-03-06 Corning Incorporated Procede et appareil servant a briser des materiaux cassants

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3629545A (en) * 1967-12-19 1971-12-21 Western Electric Co Laser substrate parting
FR2202856A1 (fr) * 1972-10-12 1974-05-10 Glaverbel
GB2139615A (en) * 1983-05-13 1984-11-14 Glaverbel Forming holes in vitreous sheets
WO1993020015A1 (fr) * 1992-04-02 1993-10-14 Fonon Technology Limited Clivage de materiaux non metalliques
WO1997007927A1 (fr) * 1995-08-31 1997-03-06 Corning Incorporated Procede et appareil servant a briser des materiaux cassants

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6919531B2 (en) 2002-03-25 2005-07-19 Agilent Technologies, Inc. Methods for producing glass substrates for use in biopolymeric microarrays
US7026573B2 (en) 2002-03-25 2006-04-11 Agilent Technologies, Inc. Methods for producing glass substrates for use in biopolymeric microarrays
RU2238918C2 (ru) * 2002-06-07 2004-10-27 Кондратенко Владимир Степанович Способ резки хрупких неметаллических материалов

Also Published As

Publication number Publication date
AU1227501A (en) 2001-05-14

Similar Documents

Publication Publication Date Title
JP3923526B2 (ja) 壊れやすい材料の分断方法および装置
TWI426057B (zh) The method of stripping angle of brittle material substrate
KR100510775B1 (ko) 레이저 광선에 의하여 깨지기 쉬운 재료로 된 소재를 급속 절단하기 위한 방법 및 장치
JP5432285B2 (ja) 面取りした端部を有する形状にガラスをレーザ加工する方法
KR100302825B1 (ko) 취성비금속재료의절단방법
US20020006765A1 (en) System for cutting brittle materials
Nisar et al. Laser glass cutting techniques—A review
EP2507182B1 (fr) Méthodes de découpe et séparation par laser de substrats en verre
US6259058B1 (en) Apparatus for separating non-metallic substrates
JP5325209B2 (ja) 脆性材料基板の加工方法
WO2007032392A1 (fr) Procédé et dispositif de traitement laser
JP5314674B2 (ja) 脆性材料基板の加工方法
JP5303238B2 (ja) 脆性材料基板の割断方法
Tsai et al. Laser cutting with controlled fracture and pre-bending applied to LCD glass separation
JP4256840B2 (ja) レーザ切断方法及びその装置
KR20020047479A (ko) 비금속재료의 레이저 절단 방법
WO2015026267A1 (fr) Procédé permettant d'arrondir les bords acérés d'objets en verre
JP2008183599A (ja) 高脆性非金属材料製の被加工物の加工方法及びその装置
JP2002241141A (ja) レーザによるガラスの加工方法及び装置
CN102765876A (zh) 一种激光自聚焦穿丝玻璃切割方法
CN1223531C (zh) 脆性的非金属材料的切割方法
KR100381165B1 (ko) 유리 절단 장치 및 그 방법
JPH11224865A (ja) 酸化物単結晶基板のレーザによる切断方法
WO2001032571A1 (fr) Commencement d'une decoupe de verre au moyen d'un laser
JP4298072B2 (ja) 硬質脆性板の割断方法

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CR CU CZ DE DK DM DZ EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP

点击 这是indexloc提供的php浏览器服务，不要输入任何密码和下载